Comparison of White Matter Maturation Rates in Young Rhesus Macaques and Humans

Motivation: Non-human primates are thought to develop 3-4 times faster than humans based on sexual maturity and death; however, there has been a lack of quantitative data to support this ratio to describe brain development. Goal(s): Our goal was to find a quantitative relationship between the rate of white matter myelination in rhesus macaques and humans. Approach: We compared rates of change in quantitative relaxometry MRI T1 values in six ROIs for rhesus macaques and human infants. Results: We found a ratio ranging from 4.7 to 6.2 in the ROIs, corresponding to 4.7-6.2 times faster white matter myelination in rhesus macaques than humans. Impact: By providing a quantitative approach to comparing early-life rhesus macaques white matter development with human infants, research that relates rhesus macaques and human brain development can make a more informed comparison, assisting researchers in translating results between species.